diff --git a/src/libstore/globals.cc b/src/libstore/globals.cc
index 9b22d54508..7b881d1d2f 100644
--- a/src/libstore/globals.cc
+++ b/src/libstore/globals.cc
@@ -61,7 +61,8 @@ void Settings::processEnvironment()
 
     string subs = getEnv("NIX_SUBSTITUTERS", "default");
     if (subs == "default") {
-        substituters.push_back(nixLibexecDir + "/nix/substituters/copy-from-other-stores.pl");
+        if (getEnv("NIX_OTHER_STORES") != "")
+            substituters.push_back(nixLibexecDir + "/nix/substituters/copy-from-other-stores.pl");
         substituters.push_back(nixLibexecDir + "/nix/substituters/download-using-manifests.pl");
         substituters.push_back(nixLibexecDir + "/nix/substituters/download-from-binary-cache.pl");
     } else